[OSGeo Africa] UTM latitude bands

[Tim Sutton]

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Hi Hanlie

On 13/08/2014 08:26, Hanlie Pretorius wrote:
> Hi,
> 
> I've noticed that GIS packages such as QGIS and libraries such as 
> PROJ4 (which QGIS uses, I think) don't use the latitude bands in
> the UTM grid.
> 
> Does anyone know why the full UTM grid with latitude bands is not 
> implemented? Does it result in any additional distortions as one
> moves away from the equator?
> 
> I have Googled about this and have not been able to find the
> answer.

I guess this is an upstream question for the epsg, gdal and proj4
projects (which we rely on for most of the projection work in QGIS). I
am not aware if it results in additional distortions as you move away
from the equator or if the bands simply provide false northings for
convenience. My limited understanding is that their distortion will
increase as you extend away in the longitudinal direction but not in
the latitudinal.

Regards

Tim

> 
> Thanks Hanlie _______________________________________________ 
> Africa mailing list Africa at lists.osgeo.org You can UNSUBSCRIBE at
> http://lists.osgeo.org/mailman/listinfo/africa
> 

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